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Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
Practical White Wine Production: Theory and Practice
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Practical White Wine Production: Theory and Practice

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Presentation by Tim Donahue and Sabrina Lueck at VinCO 2014.

Presentation by Tim Donahue and Sabrina Lueck at VinCO 2014.

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  • 1. White Wine Making Theory and Practice Tim Donahue and Sabrina Lueck
  • 2. The Walla Walla Center for Enology and Viticulture
  • 3. Hands-On Learning, World-Class Wines
  • 4. 2013 Wine Awards 2013 Muscat Ottonel - Bronze, Tri-Cities Wine Festival
 2012 Estate Semillon - Double Gold, Seattle Wine Awards; Bronze San Francisco Int'l Wine Comp.
 2012 Scholarship White - Double Gold, Seattle Wine Awards; Silver, Indy Int'l Wine Comp.
 2012 Estate Sauvignon Blanc - Top 50 Regional Wines, Seattle Times; Double Gold, Seattle Wine Awards; Silver, Indy Int'l Wine Comp.
 2012 Riesling - Silver, Indy Int'l Wine Comp.; Silver, Tri-Cities Wine Festival
 2012 Muscat Ottonel - Double Gold, Seattle Wine Awards
 2012 Mourvedre Rosé - Double Gold, Seattle Wine Awards
 2012 Estate Malbec - Bronze, Tri-Cities Wine Festival
 2012 Chardonnay - Silver, Indy Int'l Wine Comp.; Silver, Tri-Cities Wine Festival
 2012 Estate Carmenere - Double Gold and Best Carmenere, San Francisco Int'l Wine Comp.
 2012 Estate Cabernet Sauvignon Ice Wine - Double Gold, Seattle Wine Awards; Silver, Indy Int'l Wine Comp.
 2011 Syrah - Gold, Tri-Cities Wine Festival; Silver, Indy Int'l Wine Comp. 
 2011 Estate Semillon - Silver, San Francisco Chronicle Wine Comp.
 2011 Scholarship Red - Double Gold and Best Bordeaux Blend, Indy Int'l Wine Comp.; Silver, Tri-Cities Wine Festival
 2011 Estate Merlot - Silver, Indy Int'l Wine Comp.
 2011 Estate Malbec - Gold, Seattle Wine Awards; Silver, San Francisco Int'l Wine Comp.
 2011 Estate Cabernet Sauvignon - Silver, Indy Int'l Wine Comp.
 2011 Barbera Dessert Wine - Silver, Seattle Wine Awards
 2010 Syrah - Bronze, Tri-Cities Wine Festival
 2010 Estate President's Blend - Bronze, San Francisco Chronicle Wine Comp.
 2010 Estate Merlot - Silver, Seattle Wine Awards; Silver, San Francisco Chronicle Wine Comp.
 2008 Syrah - Bronze, Seattle Wine Awards
  • 5. Special Thanks Gordon Burns, Dr Rich Descenzo, and the ETS Laboratories team. Their support empowers us to be better winemakers and better educators.
  • 6. Two Part Format Sabrina 1. Review of chemical parameters and chemical/biological processes. 2. Chemical/biological impact on winemaking processes. Tim 1. Identifying issues via juice and wine analysis. 2. Application of chemical and microbiological concepts easier winemaking, better wines.
  • 7. Chemical Parameters and Winemaking “Problems” Part 1
  • 8. Key Chemical and Microbiological Concepts • The chemical parameters that we need to know are in the ETS Labs juice and chemistry panels • Knowing some key concepts empowers us to be better decision makers • Our chemistry is tied to our microbiology • Our microbiology is tied to our chemistry • Both are tied to sensory perception
  • 9. Chemical Parameters What’s in our wine?
  • 10. Main Chemical Parameters Juice (ETS Juice Panel) pH Wine (ETS Chem Panel) pH Titratable Acidity Titratable Acidity Acidity Tartaric Acid L-Malic Acid (L-Malic Acid) Potassium Potassium Brix Glucose + Fructose Glucose + Fructose α-Amino Compounds (NOPA) Sugar Nitrogen-Containing Compounds Ammonia (FAN) Yeast Assimilable Nitrogan (YAN) Free SO2 Total SO2 SO2 Molecular SO2 Volatile Acidity Acetic Acid / Ethyl Acetate
  • 11. Acid Metrics pH Titratable Acidity Reflects concentration of free H+ in solution (not a direct value) pH = -log[H+] Reflects concentration of titratable H+ H+ that is free, H+ that is part of COOH groups • • • • TA = [H+] + [-COOH] • Direct measurement of acid Direct species. Measurement Tartaric acid and malic acid • • Will influence molecular SO2 concentration Will influence microbial activity Correlation to sensory No correlation to microbial stability Correlation to sensory No correlation to microbial stability Excellent tool at juice stage
  • 12. Tartaric and Malic Acid Dissociation pKa = pH at which concentrations of ionized and partially/un-ionized species are equal
 at pKa = 2.98, [H2T] = [HT-]
 Lower pKa = stronger acid (Image: Sacks, 2010)
  • 13. pH < 3.67 H2T Predominant equilibrium H+ + HT- HT- HT- + K+ → KHT • Implications of KHT precipitation pH > 3.67 • • Decrease in TA due to loss of titratable protons (HT-) Decrease in pH due to equilibrium shift to right System wants to dissociate H2T to replace lost HT- - will release H+ H+ + T2- HT- + K+ → KHT • • • Decrease in TA due to loss of titratable protons (HT-) Increase in pH due to equilibrium shift to the left System wants to re-associate T2- and H+ to replace lost HT- will consume H+ We can predict problems by knowing and understanding our pH and [K+]! (Image: Jackson, 2008)
  • 14. Sugar • Main species - hexose sugars, glucose and fructose ! C6H12O6 → 2C2H5OH + 2CO2 • Both are converted to ethanol • Both metabolized to fructose-6-P early on in glycolysis process • Helpful to have a glu-fru measurement in juice stage • Imperative to have glu-fru measurement at supposed dryness
  • 15. Brix • Brix isn’t sugar! • • -2°B ≠ 0 g/L sugar Measure of total soluble solids • Includes non-fermentable sugars, other solids ! ºBrix x 0.6 = potential ABV (?) • Not that clean-cut • Many factors influence sugar to alcohol conversion • Brix isn’t a direct measure of sugar content
  • 16. Yeast Assimilable Nitrogen YAN = NH4+ + α-amino compounds • α-amino compounds = non-proline amino acids • Very important for both flavor production and healthfulness • • • Conceptually tied to sulfur reduction Conceptually tied to biogenic amine production Supplement low YAN with Di Ammonium Phosphate (DAP) • We need to know our numbers! • Major implications with too much or too little supplementation
  • 17. Free SO2 and Molecular SO2 molecular SO2 + H2O + H + pKa = 1.81 bisulfite HSO3 + 2H pKa = 7.2 SO2 is in a pH dependent equilibrium • Molecular SO2 - the active antimicrobial species • Bisulfite - binds to carbonyl compounds rendering them involitile • • Removal of acetaldehyde “bruised apple” aroma Sulfite - not present in significant quantity at wine pH + sulfite 2SO3
  • 18. Figure 1. The percentage of forms of free sulfite over pH 0 to 7 We live here (Henderson, 2009)
  • 19. Figure 2. Free SO2 concentration required to obtain 0.8 mg/L molecular SO2 at a given pH 140 Free SO2 Concentration 120 100 80 60 40 20 0 2.90 3.00 3.10 3.20 3.30 3.40 3.50 pH 3.60 3.70 3.80 3.90 4.00
  • 20. Volatile Acidity • Two components of volatile acidity - acetic acid and ethyl acetate • Ethyl acetate is produced via non-enzymatic esterification with ethanol • Ratio is roughly 5:1 in wine, however detection threshold of ethyl acetate is 25x higher than acetic acid
  • 21. Volatile Acidity • Acetic acid is mainly produced microbiologically • • Acetic acid bacteria, mainly acetobacter - at crush/press, fermentation (in unclean wine), and aging • S. cerevisiae - during stuck or sluggish fermentations • Lactic acid bacteria - Oenococcus oeni, Lactobacillus, or Pediococcus during MLF • • “Native” yeast, mainly Hanseniaspora uvarum - at crush/press, early fermentation Damaged berries, Pichia membranaefaciens in Sour Rot Converting sugar to acetic acid
  • 22. Winemaking “Problems” Step by step crisis management
  • 23. Stages To Discuss Stage Concern Enzymatic/chemical oxidation Crush and Press Microbial spoilage, volatile acidity production Cold Settle and Clairification Microbial spoilage, volatile acidity production Primary Fermentation Microbial spoilage Volatile acidity production Sulfur reduction Malolactic Fermentation Chemical/microbiological oxidation Volatile acidity production
  • 24. Crush and Press 1. Enzymatic/chemical oxidation 2. Microbial spoilage • Volatile acidity production • YAN depletion
  • 25. 1. Enzymatic Oxidation - Polyphenol Oxidase • Polyphenol oxidase oxidizes polyphenols! • Converts diphenol groups to quinone groups • • Groups found in caffeic acid, quercetin, B-ring of most flavonoids (condensed tannins and anthocyanins) Implications - non-enzymatic - • Quinones consume bisulfite (HSO3 ), can consume free SO2 • Quinones can “capture” thiols • • PPO browning at press - capture of Sauvignon Blanc varietal aromatics (if quinones still present when thiols are released) PPO is denatured by SO2 and alcohol • Add SO2 at press • Minimize air at press - oxidizes with O2 • PPO isn’t functional in wine
  • 26. 1. Enzymatic Oxidation - Laccase • Vector - botrytis bunch rot • Main substrate - diphenol, other groups • Not denatured by SO2, ethanol • Conflicting literature on removal • Tannin fining due to low isoelectric point of enzyme (laccase- + tannin+) (Winesecrets, 2011) • Simply bind protein with bentonite (AWRI, 2011) • Anecdotal evidence from Tim - laccase removal from Muscat Ottonel
  • 27. 1. Non-Enzymatic Oxidation • • Metal catalyzed oxidation (Cu, Fe) 2+ Cu • 3+ catalyzes formation of Fe 3+ Fe • • 2+ from Fe , and HOO• species reacts with polyphenols to form quinones SO2 binding, browning polymerization HOO• reacts with polyphenols and ethanol (in wine) • Quinone formation, aldehyde production (Danilewicz, 2007)
  • 28. 2. Microbial Spoilage • Competitive advantage of spoilage microorganisms at crush/press • • No ethanol • • Oxygen (potentially) No kill-positive S. cerevisiae Implications • Volatile acidity - sugar to acetic acid in presence of oxygen • YAN depletion - consumed by spoilage microbes • Down-the-line implications - underfed S. cerevisiae population, H2S libration
  • 29. Cold Settle and Clarification 1. Reduce biological and nonbiological turbidity 2. Obtain chemical data
  • 30. 1. Reduce Biological and Non-biological Turbidity • 1-2 punch of cold (<40F) and enzyme - drop out solids • Reduce juice turbidity • • • Fermenting “dirty” juice - higher fusel oil production, masking of aromatics Yeast produce higher reduced sulfur aromas Reduce microbial populations • Reduce microbial population = reduce potential for VA • Reduce microbial population which is consuming YAN (Riberau-Gayon, 2006)
  • 31. 2. Obtain Chemical Data • Minimum - pH, TA, Brix, YAN • High value in having L-malic and tartaric acids • TA isn’t a good indicator of acids in juice (K+ interference) • Brix, pH, and potassium give us an idea of pH shift during tartrate drop • Are we going to shift down or up?
  • 32. Fermentation 1. Volatile Acidity 2. Sulfur Reduction (Image: Napa Valley College)
  • 33. 1. Volatile Acidity Production • Did we settle microbes out? • • LABs can convert sugar to acetic acid Hanseniaspora uvarum have a competitive advantage at the beginning of ferment • Higher population than S. cerevisiae, thrive in warmth and low alcohol • Some strains can produce 25 x normal ferment production • Acetic acid will inhibit our yeast
  • 34. 2. Reduced Sulfur Production (Sacks Lecture, 2010)
  • 35. Mastering Sulfur Reduction - Go Reductive! “grapefruit, passionfruit” “passionfruit, tropical” (Curtin et al., 2008)
  • 36. Malolactic Fermentation 1. Microbial Spoilage 2. Volatile Acidity Production
  • 37. Factors Inhibiting MLF • Think TAPS (thanks Tim) • Temperature - above 14C • Alcohol - below 15% • pH - above 3.05 • SO2 - below 40 mg/L
  • 38. Practical Tasting Part 2
  • 39. Key Points • Titratable Acidity • • Pretending everything is Tartaric • • • • • Good for vineyard record keeping Depletion during MLF Potassium • • Buffer capacity • Good predictor for sensory thresholds in wine Bad for wine production decision making Malic Acid KHT stability Yeast Assimiliable Nitrogen
  • 40. Disclaimer • These wines were not made in triplicate under controlled laboratory conditions. • These wines are commercial wines, in production sized batches (2+ Tons) that are made for sale. • Please do not misconstrue the data as being academic and publishable, it is merely for educational purposes and to illustrate how a winemaker might react to a given set of conditions. :)
  • 41. Wine #1 Semillon Student Winemakers: Natalie Jones, Erin Procter, Jack Clapahm-Oeder
  • 42. First Wine: Sémillon Estate “Stan Clarke” Vineyard 1.99 g of H2M (MW134) = 2.22 g of H2T (MW150) Remember TA is expressed in “Tartaric Acid Equivalents” SO if we add up 2.22 g/L + 5.81 = 8.03 g/L of “TA”!!!!
  • 43. Production Processing Fermentation • Whole bunch pressing in an old “Willmes” press. • Fermented with high biomass yeast (SimiWhite) • Oxidative pressing • Fermented in 12°C (54°F cellar) • No SO2 additions during crushing or pressing. • DAP at 3 stages (18,14 and 10° brix) to raise YAN to 320 mg/L • 25 mg/L added at tank for cold settling. • Fermentation lasted 16 days • Enzymatically settled with pectinase • Inoculated with Enoferm Beta (for MLF) • 0.5 g/L bentonite at the tank • • Cold settled for 48 hours at <5°C (38°F). MLF conducted in cool cellar to extend process and increase levels of diacetyl. (60 days) • Racked to 6 neutral barrels
  • 44. Remember to monitor your fermentations! Brix Temperature 22 18 14 10 6 2 -2 0.0 1.4 2.0 2.4 3.0 4.1 5.1 5.4 6.0 7.0 7.4 8.0 9.0 9.4 10.0 12.0 13.1 15.1 16.0 Days Since Inoculation
  • 45. Post Fermentation Numbers • Remember that TA thing? • This influences the decision to undergo MLF! • MLF was inoculated in order to reduce the acidity to a more reasonable number. ?
  • 46. Finishing Aging • • Battonage (stirring) weekly until MLF complete. • Added 60 mg/L of SO2 post MLF • No additional bentonite, as wine was “stable” Bottling SO2 to 0.8 mg/L molecular Barrels topped weekly. • SO2 adjusted monthly. Plate and frame filtered nominally sterile to 0.46 micron • DO2 checked prior to bottling, N sparge to lower DO2 below 1.0 mg/L • Sterile bottled • Closed with screwcap with tinsaranex liner. Aged 6 months “sur-lie” • Plate and frame filtered coarse, 2.0 micron. • • • • Racked under CO2 blanket to tank 1 week prior to bottling.
  • 47. Bottling Data • MLF reduced the titratable acidity to 7.3 g/L • Low pH requires low free SO2 to obtain a good molecular SO2 • • Remember to “adapt” for DO2 during bottling. Each 1 mg/L of DO2 removes 4 mg/L of SO2
  • 48. Wine #2 Sauvignon Blanc Student Winemakers: Marcus Mejiia, Marcus Borron, Cody Janett, Stephen Moore
  • 49. Second Wine: 2012 Sauvignon Blanc Stan Clarke “Estate” Vineyard • Same harvest date as the Semillon • “TA” still doesn’t line up • Look at all of that potassium…… 3.44
  • 50. Reductive Processing
  • 51. Production Processing Fermentation • Reductively destemmed/crushed with ≈ 50 lb of CO2 “snow” per ton and 25 mg/L of SO2 added. Fermentation started with Tourlaspora delbruckii. • • After 4° brix drop, second inoculum of X-5 yeast to finish primary. • 6 hour skin contact with a cellulase enzyme • Reductively in membrane press • Waited for DAP addition until obvious H2S liberation. (WHAT?) • 25 mg/L of SO2 added during press cycles in 5mg/ L increments. • Then DAP added to raise YAN to 320 mg/L at 15° brix • Fermentation in jacketed SS tank to maintain 1° brix drop per day • Temp range between 17 to 8.5°C. • • • • • ! Transferred under CO2 to tank. Press fraction treated with 10 g/HL of PVPP then combined with free run. Enzymatically settled with pectinase 0.5 g/L bentonite at the tank Cold settled for 48 hours at <5°C (38°F). ! ! !
  • 52. Brix Temperature 22 18 14 10 6 2 -2 0 3.3 4.4 5.3 6.4 7.6 8.7 9.7 Days Since Inoculation 10.7 12.3 13.4 15.4
  • 53. Post Fermentation Numbers • Again, the TA rises, but in proportion to the actual sum of acids in the wine. • Potassium may still cause further de-acidification due to KHT formation. • Lastly, just because a hydrometer reads -2° brix, doesn’t mean you are DRY. • Confirm dryness! ?
  • 54. Finishing Aging • P+F filtered coarse, 2.0 micron. • 60 mg/L SO2 at end of primary • De-acidification/mutage trials • Racked 1 month post primary • Mutage with concentrate to 3 g/L RS • SO2 maintained at 0.8 mg/L molecular and adjusted monthly. Bottling • • • • • P+F filtered nominally sterile to 0.46 micron Heat stability verified via Bentotest™ Bentonite added at 0.25 g/L (after trials) • Racked under CO2 blanket to tank 1 week prior to bottling. DO2 checked prior to bottling, N sparge to lower DO2 below 1.0 mg/L • Sterile bottled closed with screwcap with tin-saranex liner. Cold stabilized via 2 week cold hold at -2°C
  • 55. Bottling Data • Note lower TA post cold stabilization. • Higher SO2 additions required because of higher SO2 added at crush.
  • 56. Wine #3 Muscat Ottonel Grown by Chef Greg Schnorr
  • 57. Third Wine: 2013 Muscat Ottonel Schnorr Vineyard • Juice Panel: When your pH is higher than your TA… • 17° Brix, powdery mildew. Good times!
  • 58. Production Notes Day 1 • 1 g/L malic acid added (TA equivalent) • 100 mg/L SO2 at the crusher • 25 kg/T of CO2 snow • Juice split 70% for wine • Cold soak in press for 24 hours • 30% for juice • Juice sorbated 150mg/L as sorbic acid Day 2 Day 4 • Pressed reductively • 100 mg/L SO2 • Laccase positive • Moved to fridge • 1 g/L Bentonite • Laccase check – clean! • 0.1 g/L “FT–Rouge Soft” • Rack to fermentation tank under blanket of CO2 • Pectinase for settling • Inoculated with Zymaflore Alpha (Tourlaspora delbruckii) • Finished with QA-23 • 100 mg/L Dap addition at 2nd inoculation. Day 3 • 60 g/L of C+H’s finest! • 1 g/L tartaric Acid added
  • 59. Brix Temperature 22 18 14 10 6 2 -2 0 1.8 2.9 4 5.7 6.7 8.6 10 11.1 12 Days Since Inoculation 13 13.9 15.6 16.6 17.6
  • 60. Production Notes Day 14-24 - Cold stabilization (sort of….) Day 26 • Confirm sorbate level via ETS • Cellulose gum added at 1ml/L tartrates + bubbles = :( Day 24 - Crossflow filter Day 25 • Mutage (juice add back) • Day 28 - Sterile bottle on 6 spout hand bottling line. Sterile filter (nominal) Day 29 - Sales begin….. • • Potassium sorbate bump to 120 mg/L SO2 bump to 1.0 mg/L molecular SO2 Bigger goal – sell it out ASAP to pay for your red wine habit….
  • 61. Bottling Data • Sold out by Christmas • Initial sales in the first week covered all production costs. • Sales by Christmas covered ALL barrel expenses for College Cellars…. • Cash-flow winemaking!
  • 62. References Henderson, P. 2009. Sulfur Dioxide. Practical Winery and Vineyard Journal. January/February. Danilewicz, J.C. 2007. Interaction of Sulfur Dioxide, Polyphenols, and Oxygen in a Wine-Model System: Central Role of Iron and Copper. Am. J. Enol. Vitic. 58:53-60 Ribereau-Gayon, P., Dubourdieu, D., Doneche, B., and A. Lonvaud. 2006. Handbook of Enology Volume 1 The Microbiology of Wine and Vinifications. John Wiley & Sons, West Sussex, UK. Curtin, C., King, E., Kievit, R.L., Ugliano, M., Henschke, P., and P. Chambers. 2008. Optimizing Wine Quality through the Application of Flavour-Active Yeast Strains and Nutrients. In Proceedings of Les XXes Entretiens Scientifiques Lallemand. pp 25-35. Lallemand SAS, Toulouse. Sweigers, J.H., Bartowsky, E.J., Henschke, P.A. and I.S Pretorius. 2005. Yeast and bacterial modulation of wine aroma and flavour. Australian Journal of Grape and Wine Research. 11: 139-173. Jackson, R.S. 2008. Wine Science Principles and Applications. Academic Press, Burlington, MA.

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